experimental patch including XEP-248 (thanks to Brian Cully)

SVN Revision: 2157

18 files changed, 642 insertions, 105 deletions

diff --git a/src/mod_pubsub/Makefile.win32 b/src/mod_pubsub/Makefile.win32
index f981329c9..d3cdcc499 100644
--- a/src/mod_pubsub/Makefile.win32
+++ b/src/mod_pubsub/Makefile.win32
@@ -4,7 +4,7 @@ include ..\Makefile.inc
 EFLAGS = -I .. -pz ..
 
 OUTDIR = ..
-BEAMS = ..\gen_pubsub_node.beam ..\gen_pubsub_nodetree.beam ..\mod_pubsub.beam ..\nodetree_default.beam ..\nodetree_virtual.beam ..\node_buddy.beam ..\node_club.beam ..\node_default.beam ..\node_dispatch.beam ..\node_pep.beam ..\node_private.beam ..\node_public.beam
+BEAMS = ..\gen_pubsub_node.beam ..\gen_pubsub_nodetree.beam ..\mod_pubsub.beam ..\nodetree_tree.beam ..\nodetree_virtual.beam ..\node_buddy.beam ..\node_club.beam ..\node_hometree.beam ..\node_dispatch.beam ..\node_pep.beam ..\node_private.beam ..\node_public.beam
 
 ALL : $(BEAMS)
 
@@ -20,8 +20,8 @@ $(OUTDIR)\gen_pubsub_nodetree.beam : gen_pubsub_nodetree.erl
 $(OUTDIR)\mod_pubsub.beam : mod_pubsub.erl
 	erlc -W $(EFLAGS) -o $(OUTDIR) mod_pubsub.erl
 
-$(OUTDIR)\nodetree_default.beam : nodetree_default.erl
-	erlc -W $(EFLAGS) -o $(OUTDIR) nodetree_default.erl
+$(OUTDIR)\nodetree_tree.beam : nodetree_tree.erl
+	erlc -W $(EFLAGS) -o $(OUTDIR) nodetree_tree.erl
 
 $(OUTDIR)\nodetree_virtual.beam : nodetree_virtual.erl
 	erlc -W $(EFLAGS) -o $(OUTDIR) nodetree_virtual.erl
@@ -32,8 +32,8 @@ $(OUTDIR)\node_buddy.beam : node_buddy.erl
 $(OUTDIR)\node_club.beam : node_club.erl
 	erlc -W $(EFLAGS) -o $(OUTDIR) node_club.erl
 
-$(OUTDIR)\node_default.beam : node_default.erl
-	erlc -W $(EFLAGS) -o $(OUTDIR) node_default.erl
+$(OUTDIR)\node_hometree.beam : node_hometree.erl
+	erlc -W $(EFLAGS) -o $(OUTDIR) node_hometree.erl
 
 $(OUTDIR)\node_dispatch.beam : node_dispatch.erl
 	erlc -W $(EFLAGS) -o $(OUTDIR) node_dispatch.erl
diff --git a/src/mod_pubsub/gen_pubsub_nodetree.erl b/src/mod_pubsub/gen_pubsub_nodetree.erl
index f012b3d0b..f55694500 100644
--- a/src/mod_pubsub/gen_pubsub_nodetree.erl
+++ b/src/mod_pubsub/gen_pubsub_nodetree.erl
@@ -47,6 +47,8 @@ behaviour_info(callbacks) ->
 	 {get_node, 1},
 	 {get_nodes, 2},
 	 {get_nodes, 1},
+	 {get_parentnodes, 3},
+	 {get_parentnodes_tree, 3},
 	 {get_subnodes, 3},
 	 {get_subnodes_tree, 3},
 	 {create_node, 5},
diff --git a/src/mod_pubsub/mod_pubsub.erl b/src/mod_pubsub/mod_pubsub.erl
index af3f76f62..b36d1a3ff 100644
--- a/src/mod_pubsub/mod_pubsub.erl
+++ b/src/mod_pubsub/mod_pubsub.erl
@@ -80,7 +80,7 @@
 	 get_items/2,
 	 get_item/3,
 	 get_cached_item/2,
-	 broadcast_stanza/7,
+	 broadcast_stanza/8,
 	 get_configure/5,
 	 set_configure/5,
 	 tree_action/3,
@@ -304,7 +304,7 @@ update_node_database(Host, ServerHost) ->
 				  mnesia:delete({pubsub_node, NodeId}),
 				  {[#pubsub_node{nodeid = NodeId,
 						id = NodeIdx,
-						parent = element(2, ParentId),
+						parents = [element(2, ParentId)],
 						owners = Owners,
 						options = Options} |
 				   RecList], NodeIdx + 1}
@@ -334,12 +334,12 @@ update_node_database(Host, ServerHost) ->
 		    #pubsub_node{
 			nodeid = NodeId,
 			id = 0,
-			parent = Parent,
+			parents = [Parent],
 			type = Type,
 			owners = Owners,
 			options = Options}
 		end,
-	    mnesia:transform_table(pubsub_node, F, [nodeid, id, parent, type, owners, options]),
+	    mnesia:transform_table(pubsub_node, F, [nodeid, id, parents, type, owners, options]),
 	    FNew = fun() ->
 		lists:foldl(fun(#pubsub_node{nodeid = NodeId} = PubsubNode, NodeIdx) ->
 		    mnesia:write(PubsubNode#pubsub_node{id = NodeIdx}),
@@ -371,6 +371,17 @@ update_node_database(Host, ServerHost) ->
 		    ?ERROR_MSG("Problem updating Pubsub node tables:~n~p",
 			       [Reason])
 	    end;
+	[nodeid, id, parent, type, owners, options] ->
+	    F = fun({pubsub_node, NodeId, Id, Parent, Type, Owners, Options}) ->
+		    #pubsub_node{
+			nodeid = NodeId,
+			id = Id,
+			parents = [Parent],
+			type = Type,
+			owners = Owners,
+			options = Options}
+		end,
+	    mnesia:transform_table(pubsub_node, F, [nodeid, id, parents, type, owners, options]);
 	_ ->
 	    ok
     end.
@@ -1443,6 +1454,12 @@ replace_subscription_helper(_, OldSub, Acc) ->
 -define(STRINGXFIELD(Label, Var, Val),
 	?XFIELD("text-single", Label, Var, Val)).
 
+-define(STRINGMXFIELD(Label, Var, Vals),
+	{xmlelement, "field", [{"type", "text-multi"},
+				{"label", translate:translate(Lang, Label)},
+				{"var", Var}],
+			[{xmlelement, "value", [], [{xmlcdata, V}]} || V <- Vals]}).
+
 -define(XFIELDOPT(Type, Label, Var, Val, Opts),
 	{xmlelement, "field", [{"type", Type},
 			       {"label", translate:translate(Lang, Label)},
@@ -1601,10 +1618,14 @@ delete_node(_Host, [], _Owner) ->
     {error, ?ERR_NOT_ALLOWED};
 delete_node(Host, Node, Owner) ->
     Action = fun(#pubsub_node{type = Type, id = NodeId}) ->
+		     SubsByDepth = get_collection_subscriptions(Host, Node),
 		     case node_call(Type, get_affiliation, [NodeId, Owner]) of
 			 {result, owner} ->
 			     Removed = tree_call(Host, delete_node, [Host, Node]),
-			     node_call(Type, delete_node, [Removed]);
+			     case node_call(Type, delete_node, [Removed]) of
+				{result, Res} -> {result, {SubsByDepth, Res}};
+				Error	 -> Error
+			     end;
 			 _ ->
 			     %% Entity is not an owner
 			     {error, ?ERR_FORBIDDEN}
@@ -1612,27 +1633,26 @@ delete_node(Host, Node, Owner) ->
 	     end,
     Reply = [],
     case transaction(Host, Node, Action, transaction) of
-	{result, {_, {Result, broadcast, Removed}}} ->
-	    lists:foreach(fun({RNode, RSubscriptions}) ->
+	{result, {_, {SubsByDepth, {Result, broadcast, Removed}}}} ->
+	    lists:foreach(fun({RNode, _RSubscriptions}) ->
 		{RH, RN} = RNode#pubsub_node.nodeid,
 		NodeId = RNode#pubsub_node.id,
 		Type = RNode#pubsub_node.type,
 		Options = RNode#pubsub_node.options,
-		broadcast_removed_node(RH, RN, NodeId, Type, Options, RSubscriptions),
-		unset_cached_item(RH, NodeId)
+		broadcast_removed_node(RH, RN, NodeId, Type, Options, SubsByDepth)
 	    end, Removed),
 	    case Result of
 		default -> {result, Reply};
 		_ -> {result, Result}
 	    end;
-	{result, {_, {Result, _Removed}}} ->
+	{result, {_, {_, {Result, _Removed}}}} ->
 	    case Result of
 		default -> {result, Reply};
 		_ -> {result, Result}
 	    end;
-	{result, {_, default}} ->
+	{result, {_, {_, default}}} ->
 	    {result, Reply};
-	{result, {_, Result}} ->
+	{result, {_, {_, Result}}} ->
 	    {result, Result};
 	Error ->
 	    Error
@@ -2605,19 +2625,28 @@ service_jid(Host) ->
 
 %% @spec (LJID, PresenceDelivery) -> boolean()
 %%	LJID = jid()
+%%	NotifyType = items | nodes
+%%	Depth = integer()
 %%	NodeOptions = [{atom(), term()}]
 %%	SubOptions = [{atom(), term()}]
 %% @doc <p>Check if a notification must be delivered or not based on
 %% node and subscription options.</p>
-is_to_deliver(LJID, NodeOptions, SubOptions) ->
-    sub_to_deliver(LJID, SubOptions) andalso node_to_deliver(LJID, NodeOptions).
-
-sub_to_deliver(_LJID, SubOptions) ->
-    lists:all(fun sub_option_can_deliver/1, SubOptions).
-
-sub_option_can_deliver({deliver, false}) -> false;
-sub_option_can_deliver({expire, When})   -> now() < When;
-sub_option_can_deliver(_)		-> true.
+is_to_deliver(LJID, NotifyType, Depth, NodeOptions, SubOptions) ->
+    sub_to_deliver(LJID, NotifyType, Depth, SubOptions)
+	andalso node_to_deliver(LJID, NodeOptions).
+
+sub_to_deliver(_LJID, NotifyType, Depth, SubOptions) ->
+    lists:all(fun (Option) ->
+		      sub_option_can_deliver(NotifyType, Depth, Option)
+	      end, SubOptions).
+
+sub_option_can_deliver(items, _, {subscription_type, nodes}) -> false;
+sub_option_can_deliver(nodes, _, {subscription_type, items}) -> false;
+sub_option_can_deliver(_, _, {subscription_depth, all})      -> true;
+sub_option_can_deliver(_, Depth, {subscription_depth, D})    -> Depth < D;
+sub_option_can_deliver(_, _, {deliver, false})	       -> false;
+sub_option_can_deliver(_, _, {expire, When})		 -> now() < When;
+sub_option_can_deliver(_, _, _)			      -> true.
 
 node_to_deliver(LJID, NodeOptions) ->
     PresenceDelivery = get_option(NodeOptions, presence_based_delivery),
@@ -2652,11 +2681,8 @@ event_stanza(Els) ->
 
 broadcast_publish_item(Host, Node, NodeId, Type, NodeOptions, Removed, ItemId, _From, Payload) ->
     %broadcast(Host, Node, NodeId, NodeOptions, none, true, "items", ItemEls)
-    case node_action(Host, Type, get_node_subscriptions, [NodeId]) of
-	{result, []} -> 
-	    {result, false};
-	{result, Subs} ->
-	    SubOptions = get_options_for_subs(Host, Node, NodeId, Subs),
+    case get_collection_subscriptions(Host, Node) of
+	SubsByDepth when is_list(SubsByDepth) ->
 	    Content = case get_option(NodeOptions, deliver_payloads) of
 		true -> Payload;
 		false -> []
@@ -2665,7 +2691,7 @@ broadcast_publish_item(Host, Node, NodeId, Type, NodeOptions, Removed, ItemId, _
 		[{xmlelement, "items", nodeAttr(Node),
 		    [{xmlelement, "item", itemAttr(ItemId), Content}]}]),
 	    broadcast_stanza(Host, Node, NodeId, Type,
-			     NodeOptions, SubOptions, Stanza),
+			     NodeOptions, SubsByDepth, items, Stanza),
 	    case Removed of
 		[] ->
 		    ok;
@@ -2676,8 +2702,8 @@ broadcast_publish_item(Host, Node, NodeId, Type, NodeOptions, Removed, ItemId, _
 				[{xmlelement, "items", nodeAttr(Node),
 				    [{xmlelement, "retract", itemAttr(RId), []} || RId <- Removed]}]),
 			    broadcast_stanza(Host, Node, NodeId, Type,
-					     NodeOptions, SubOptions,
-					     RetractStanza);
+					     NodeOptions, SubsByDepth,
+					     items, RetractStanza);
 			_ ->
 			    ok
 		    end
@@ -2695,16 +2721,13 @@ broadcast_retract_items(Host, Node, NodeId, Type, NodeOptions, ItemIds, ForceNot
     %broadcast(Host, Node, NodeId, NodeOptions, notify_retract, ForceNotify, "retract", RetractEls)
     case (get_option(NodeOptions, notify_retract) or ForceNotify) of
 	true ->
-	    case node_action(Host, Type, get_node_subscriptions, [NodeId]) of
-		{result, []} -> 
-		    {result, false};
-		{result, Subs} ->
-		    SubOptions = get_options_for_subs(Host, Node, NodeId, Subs),
+	    case get_collection_subscriptions(Host, Node) of
+		SubsByDepth when is_list(SubsByDepth) ->
 		    Stanza = event_stanza(
 			[{xmlelement, "items", nodeAttr(Node),
 			    [{xmlelement, "retract", itemAttr(ItemId), []} || ItemId <- ItemIds]}]),
 		    broadcast_stanza(Host, Node, NodeId, Type,
-				     NodeOptions, SubOptions, Stanza),
+				     NodeOptions, SubsByDepth, items, Stanza),
 		    {result, true};
 		_ ->
 		    {result, false}
@@ -2717,16 +2740,13 @@ broadcast_purge_node(Host, Node, NodeId, Type, NodeOptions) ->
     %broadcast(Host, Node, NodeId, NodeOptions, notify_retract, false, "purge", [])
     case get_option(NodeOptions, notify_retract) of
 	true ->
-	    case node_action(Host, Type, get_node_subscriptions, [NodeId]) of
-		{result, []} -> 
-		    {result, false};
-		{result, Subs} ->
-		    SubOptions = get_options_for_subs(Host, Node, NodeId, Subs),
+	    case get_collection_subscriptions(Host, Node) of
+		SubsByDepth when is_list(SubsByDepth) ->
 		    Stanza = event_stanza(
 			[{xmlelement, "purge", nodeAttr(Node),
 			    []}]),
 		    broadcast_stanza(Host, Node, NodeId, Type,
-				     NodeOptions, SubOptions, Stanza),
+				     NodeOptions, SubsByDepth, nodes, Stanza),
 		    {result, true};
 		_ -> 
 		    {result, false}
@@ -2735,20 +2755,19 @@ broadcast_purge_node(Host, Node, NodeId, Type, NodeOptions) ->
 	    {result, false}
     end.
 
-broadcast_removed_node(Host, Node, NodeId, Type, NodeOptions, Subs) ->
+broadcast_removed_node(Host, Node, NodeId, Type, NodeOptions, SubsByDepth) ->
     %broadcast(Host, Node, NodeId, NodeOptions, notify_delete, false, "delete", [])
     case get_option(NodeOptions, notify_delete) of
 	true ->
-	    case Subs of
+	    case SubsByDepth of
 		[] -> 
 		    {result, false};
 		_ ->
-		    SubOptions = get_options_for_subs(Host, Node, NodeId, Subs),
 		    Stanza = event_stanza(
 			[{xmlelement, "delete", nodeAttr(Node),
 			    []}]),
 		    broadcast_stanza(Host, Node, NodeId, Type,
-				     NodeOptions, SubOptions, Stanza),
+				     NodeOptions, SubsByDepth, nodes, Stanza),
 		    {result, true}
 	    end;
 	_ ->
@@ -2759,11 +2778,8 @@ broadcast_config_notification(Host, Node, NodeId, Type, NodeOptions, Lang) ->
     %broadcast(Host, Node, NodeId, NodeOptions, notify_config, false, "items", ConfigEls)
     case get_option(NodeOptions, notify_config) of
 	true ->
-	    case node_action(Host, Type, get_node_subscriptions, [NodeId]) of
-		{result, []} -> 
-		    {result, false};
-		{result, Subs} ->
-		    SubOptions = get_options_for_subs(Host, Node, NodeId, Subs),
+	    case get_collection_subscriptions(Host, Node) of
+		SubsByDepth when is_list(SubsByDepth) ->
 		    Content = case get_option(NodeOptions, deliver_payloads) of
 			true ->
 			    [{xmlelement, "x", [{"xmlns", ?NS_XDATA}, {"type", "form"}],
@@ -2775,7 +2791,7 @@ broadcast_config_notification(Host, Node, NodeId, Type, NodeOptions, Lang) ->
 			[{xmlelement, "items", nodeAttr(Node),
 			    [{xmlelement, "item", itemAttr("configuration"), Content}]}]),
 		    broadcast_stanza(Host, Node, NodeId, Type,
-				     NodeOptions, SubOptions, Stanza),
+				     NodeOptions, SubsByDepth, nodes, Stanza),
 		    {result, true};
 		_ -> 
 		    {result, false}
@@ -2784,6 +2800,28 @@ broadcast_config_notification(Host, Node, NodeId, Type, NodeOptions, Lang) ->
 	    {result, false}
     end.
 
+get_collection_subscriptions(Host, Node) ->
+    case mnesia:transaction(fun tree_call/3,
+			    [Host, get_parentnodes_tree,
+			     [Host, Node, service_jid(Host)]]) of
+	{atomic, NodesByDepth} when is_list(NodesByDepth) ->
+	    lists:map(fun ({Depth, Nodes}) ->
+			      {Depth, [{N, get_node_subs(N)} || N <- Nodes]}
+		      end, NodesByDepth);
+	Other ->
+	    Other
+    end.
+
+get_node_subs(#pubsub_node{type   = Type,
+			   nodeid = {Host, Node},
+			   id     = NodeID}) ->
+    case node_action(Host, Type, get_node_subscriptions, [NodeID]) of
+	{result, Subs} ->
+	    get_options_for_subs(Host, Node, NodeID, Subs);
+	Other ->
+	    Other
+    end.
+
 % TODO: merge broadcast code that way
 %broadcast(Host, Node, NodeId, Type, NodeOptions, Feature, Force, ElName, SubEls) ->
 %    case (get_option(NodeOptions, Feature) or Force) of
@@ -2802,15 +2840,14 @@ broadcast_config_notification(Host, Node, NodeId, Type, NodeOptions, Lang) ->
 %	    {result, false}
 %    end
 
-broadcast_stanza(Host, Node, _NodeId, _Type, NodeOptions, Subs, Stanza) ->
+broadcast_stanza(Host, Node, _NodeId, _Type, NodeOptions, SubsByDepth, NotifyType, Stanza) ->
     %AccessModel = get_option(NodeOptions, access_model),
     BroadcastAll = get_option(NodeOptions, broadcast_all_resources), %% XXX this is not standard, but usefull
     From = service_jid(Host),
     %% Handles explicit subscriptions
-    DeliverSubs = lists:filter(fun({LJID, _Node, SubOptions}) ->
-				       is_to_deliver(LJID, NodeOptions, SubOptions)
-			       end, Subs),
-    lists:foreach(fun({LJID, _Node, _SubOptions}) ->
+    FilteredSubsByDepth = depths_to_deliver(NotifyType, SubsByDepth),
+    NodesByJID = collate_subs_by_jid(FilteredSubsByDepth),
+    lists:foreach(fun ({LJID, Nodes}) ->
 			  LJIDs = case BroadcastAll of
 				      true ->
 					  {U, S, _} = LJID,
@@ -2818,10 +2855,11 @@ broadcast_stanza(Host, Node, _NodeId, _Type, NodeOptions, Subs, Stanza) ->
 				      false ->
 					  [LJID]
 				  end,
+			  SHIMStanza = add_headers(Stanza, collection_shim(Node, Nodes)),
 			  lists:foreach(fun(To) ->
-						ejabberd_router ! {route, From, jlib:make_jid(To), Stanza}
+						ejabberd_router ! {route, From, jlib:make_jid(To), SHIMStanza}
 					end, LJIDs)
-		  end, DeliverSubs),
+		  end, NodesByJID),
     %% Handles implicit presence subscriptions
     case Host of
 	{LUser, LServer, LResource} ->
@@ -2869,6 +2907,37 @@ broadcast_stanza(Host, Node, _NodeId, _Type, NodeOptions, Subs, Stanza) ->
 	    ok
     end.
 
+depths_to_deliver(NotifyType, SubsByDepth) ->
+    NodesToDeliver =
+	fun (Depth, Node, Subs, Acc) ->
+		lists:foldl(fun ({LJID, _Node, SubOptions} = S, Acc2) ->
+				     case is_to_deliver(LJID, NotifyType, Depth,
+							Node#pubsub_node.options,
+							SubOptions) of
+					 true  -> [S | Acc2];
+					 false -> Acc2
+				     end
+			     end, Acc, Subs)
+	end,
+
+    DepthsToDeliver =
+	fun ({Depth, SubsByNode}, Acc) ->
+		lists:foldl(fun ({Node, Subs}, Acc2) ->
+				    NodesToDeliver(Depth, Node, Subs, Acc2)
+			    end, Acc, SubsByNode)
+	end,
+
+    lists:foldl(DepthsToDeliver, [], SubsByDepth).
+
+collate_subs_by_jid(SubsByDepth) ->
+    lists:foldl(fun ({JID, Node, _Options}, Acc) ->
+			OldNodes = case lists:keysearch(JID, 1, Acc) of
+				       {value, {JID, Nodes}} -> Nodes;
+				       false		 -> []
+				   end,
+			lists:keystore(JID, 1, Acc, {JID, [Node | OldNodes]})
+		end, [], SubsByDepth).
+
 %% If we don't know the resource, just pick first if any
 %% If no resource available, check if caps anyway (remote online)
 user_resources(User, Server) ->
@@ -3000,6 +3069,10 @@ max_items(Options) ->
 	?LISTMXFIELD(Label, "pubsub#" ++ atom_to_list(Var),
 		     get_option(Options, Var), Opts)).
 
+-define(NLIST_CONFIG_FIELD(Label, Var),
+	?STRINGMXFIELD(Label, "pubsub#" ++ atom_to_list(Var),
+		       [node_to_string(N) || N <- get_option(Options, Var)])).
+
 get_configure_xfields(_Type, Options, Lang, Groups) ->
     [?XFIELD("hidden", "", "FORM_TYPE", ?NS_PUBSUB_NODE_CONFIG),
      ?BOOL_CONFIG_FIELD("Deliver payloads with event notifications", deliver_payloads),
@@ -3020,7 +3093,8 @@ get_configure_xfields(_Type, Options, Lang, Groups) ->
      ?INTEGER_CONFIG_FIELD("Max payload size in bytes", max_payload_size),
      ?ALIST_CONFIG_FIELD("When to send the last published item", send_last_published_item,
 			 [never, on_sub, on_sub_and_presence]),
-     ?BOOL_CONFIG_FIELD("Only deliver notifications to available users", presence_based_delivery)
+     ?BOOL_CONFIG_FIELD("Only deliver notifications to available users", presence_based_delivery),
+     ?NLIST_CONFIG_FIELD("The collections with which a node is affiliated", collection)
     ].
 
 %%<p>There are several reasons why the node configuration request might fail:</p>
@@ -3052,8 +3126,10 @@ set_configure(Host, Node, From, Els, Lang) ->
 							  end,
 						case set_xoption(XData, OldOpts) of
 						    NewOpts when is_list(NewOpts) ->
-							tree_call(Host, set_node, [N#pubsub_node{options = NewOpts}]),
-							{result, ok};
+							case tree_call(Host, set_node, [N#pubsub_node{options = NewOpts}]) of
+							    ok -> {result, ok};
+							    Err -> Err
+							end;
 						    Err ->
 							Err
 						end
@@ -3166,6 +3242,9 @@ set_xoption([{"pubsub#type", Value} | Opts], NewOpts) ->
     ?SET_STRING_XOPT(type, Value);
 set_xoption([{"pubsub#body_xslt", Value} | Opts], NewOpts) ->
     ?SET_STRING_XOPT(body_xslt, Value);
+set_xoption([{"pubsub#collection", Value} | Opts], NewOpts) ->
+    NewValue = [string_to_node(V) || V <- Value],
+    ?SET_LIST_XOPT(collection, NewValue);
 set_xoption([_ | Opts], NewOpts) ->
     % skip unknown field
     set_xoption(Opts, NewOpts).
@@ -3257,7 +3336,7 @@ features() ->
 	 "member-affiliation",   % RECOMMENDED
 	 %TODO "meta-data",   % RECOMMENDED
 	 % see plugin "modify-affiliations",   % OPTIONAL
-	 %TODO "multi-collection",   % OPTIONAL
+	 % see plugin "multi-collection",   % OPTIONAL
 	 % see plugin "multi-subscribe",   % OPTIONAL
 	 % see plugin "outcast-affiliation",   % RECOMMENDED
 	 % see plugin "persistent-items",   % RECOMMENDED
@@ -3395,3 +3474,10 @@ itemsEls(Items) ->
     lists:map(fun(#pubsub_item{itemid = {ItemId, _}, payload = Payload}) ->
 	{xmlelement, "item", itemAttr(ItemId), Payload}
     end, Items).
+
+add_headers({xmlelement, Name, Attrs, Els}, Headers) ->
+    {xmlelement, Name, Attrs, Els ++ Headers}.
+
+collection_shim(Node, Nodes) ->
+    [{xmlelement, "header", [{"name", "Collection"}],
+      [{xmlcdata, node_to_string(N)}]} || N <- Nodes -- [Node]].
diff --git a/src/mod_pubsub/node.template b/src/mod_pubsub/node.template
index 336c547a9..534c18226 100644
--- a/src/mod_pubsub/node.template
+++ b/src/mod_pubsub/node.template
@@ -65,7 +65,8 @@
 	 get_items/2,
 	 get_item/7,
 	 get_item/2,
-	 set_item/1
+	 set_item/1,
+	 get_item_name/3
 	]).
 
 
@@ -76,8 +77,7 @@ terminate(Host, ServerHost) ->
     node_hometree:terminate(Host, ServerHost).
 
 options() ->
-    [{node_type, __TO_BE_DEFINED__},
-     {deliver_payloads, true},
+    [{deliver_payloads, true},
      {notify_config, false},
      {notify_delete, false},
      {notify_retract, true},
@@ -118,8 +118,8 @@ create_node(NodeId, Owner) ->
 delete_node(Removed) ->
     node_hometree:delete_node(Removed).
 
-subscribe_node(NodeId, Sender, Subscriber, AccessModel, SendLast, PresenceSubscription, RosterGroup) ->
-    node_hometree:subscribe_node(NodeId, Sender, Subscriber, AccessModel, SendLast, PresenceSubscription, RosterGroup).
+subscribe_node(NodeId, Sender, Subscriber, AccessModel, SendLast, PresenceSubscription, RosterGroup, Options) ->
+    node_hometree:subscribe_node(NodeId, Sender, Subscriber, AccessModel, SendLast, PresenceSubscription, RosterGroup, Options).
 
 unsubscribe_node(NodeId, Sender, Subscriber, SubID) ->
     node_hometree:unsubscribe_node(NodeId, Sender, Subscriber, SubID).
@@ -158,7 +158,7 @@ get_subscriptions(NodeId, Owner) ->
     node_hometree:get_subscriptions(NodeId, Owner).
 
 set_subscriptions(NodeId, Owner, Subscriptions) ->
-    node_hometree:set_subscriptions(NodeId, Owner, Subscription).
+    node_hometree:set_subscriptions(NodeId, Owner, Subscriptions).
 
 get_states(NodeId) ->
     node_hometree:get_states(NodeId).
@@ -172,7 +172,7 @@ set_state(State) ->
 get_items(NodeId, From) ->
     node_hometree:get_items(NodeId, From).
 
-get_items(NodeId, JID, AccessModel, PresenceSubscription, RosterGroup, SubId)
+get_items(NodeId, JID, AccessModel, PresenceSubscription, RosterGroup, SubId) ->
     node_hometree:get_items(NodeId, JID, AccessModel, PresenceSubscription, RosterGroup, SubId).
     
 get_item(NodeId, ItemId) ->
@@ -183,3 +183,6 @@ get_item(NodeId, ItemId, JID, AccessModel, PresenceSubscription, RosterGroup, Su
     
 set_item(Item) ->
     node_hometree:set_item(Item).
+
+get_item_name(Host, Node, Id) ->
+    node_hometree:get_item_name(Host, Node, Id).
diff --git a/src/mod_pubsub/node_buddy.erl b/src/mod_pubsub/node_buddy.erl
index 0094674e7..2e8dd0249 100644
--- a/src/mod_pubsub/node_buddy.erl
+++ b/src/mod_pubsub/node_buddy.erl
@@ -78,8 +78,7 @@ terminate(Host, ServerHost) ->
     node_hometree:terminate(Host, ServerHost).
 
 options() ->
-    [{node_type, buddy},
-     {deliver_payloads, true},
+    [{deliver_payloads, true},
      {notify_config, false},
      {notify_delete, false},
      {notify_retract, true},
diff --git a/src/mod_pubsub/node_club.erl b/src/mod_pubsub/node_club.erl
index 6bbece021..91ff520c6 100644
--- a/src/mod_pubsub/node_club.erl
+++ b/src/mod_pubsub/node_club.erl
@@ -78,8 +78,7 @@ terminate(Host, ServerHost) ->
     node_hometree:terminate(Host, ServerHost).
 
 options() ->
-    [{node_type, club},
-     {deliver_payloads, true},
+    [{deliver_payloads, true},
      {notify_config, false},
      {notify_delete, false},
      {notify_retract, true},
diff --git a/src/mod_pubsub/node_dag.erl b/src/mod_pubsub/node_dag.erl
new file mode 100644
index 000000000..954a26a95
--- /dev/null
+++ b/src/mod_pubsub/node_dag.erl
@@ -0,0 +1,154 @@
+%%% ====================================================================
+%%% ``The contents of this file are subject to the Erlang Public License,
+%%% Version 1.1, (the "License"); you may not use this file except in
+%%% compliance with the License. You should have received a copy of the
+%%% Erlang Public License along with this software. If not, it can be
+%%% retrieved via the world wide web at http://www.erlang.org/.
+%%%
+%%% Software distributed under the License is distributed on an "AS IS"
+%%% basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
+%%% the License for the specific language governing rights and limitations
+%%% under the License.
+%%%
+%%% @author Brian Cully <bjc@kublai.com>
+%%% @version {@vsn}, {@date} {@time}
+%%% @end
+%%% ====================================================================
+
+-module(node_dag).
+-author('bjc@kublai.com').
+
+-include("pubsub.hrl").
+-include("jlib.hrl").
+
+-behaviour(gen_pubsub_node).
+
+%% API definition
+-export([init/3, terminate/2,
+	 options/0, features/0,
+	 create_node_permission/6,
+	 create_node/2,
+	 delete_node/1,
+	 purge_node/2,
+	 subscribe_node/8,
+	 unsubscribe_node/4,
+	 publish_item/6,
+	 delete_item/4,
+	 remove_extra_items/3,
+	 get_entity_affiliations/2,
+	 get_node_affiliations/1,
+	 get_affiliation/2,
+	 set_affiliation/3,
+	 get_entity_subscriptions/2,
+	 get_node_subscriptions/1,
+	 get_subscriptions/2,
+	 set_subscriptions/3,
+	 get_states/1,
+	 get_state/2,
+	 set_state/1,
+	 get_items/6,
+	 get_items/2,
+	 get_item/7,
+	 get_item/2,
+	 set_item/1,
+	 get_item_name/3]).
+
+
+init(Host, ServerHost, Opts) ->
+    node_hometree:init(Host, ServerHost, Opts).
+
+terminate(Host, ServerHost) ->
+    node_hometree:terminate(Host, ServerHost).
+
+options() ->
+    [{node_type, leaf} | node_hometree:options()].
+
+features() ->
+    ["multi-collection" | node_hometree:features()].
+
+create_node_permission(_Host, _ServerHost, _Node, _ParentNode,
+		       _Owner, _Access) ->
+    {result, true}.
+
+create_node(NodeID, Owner) ->
+    node_hometree:create_node(NodeID, Owner).
+
+delete_node(Removed) ->
+    node_hometree:delete_node(Removed).
+
+subscribe_node(NodeID, Sender, Subscriber, AccessModel,
+	       SendLast, PresenceSubscription, RosterGroup, Options) ->
+    node_hometree:subscribe_node(NodeID, Sender, Subscriber, AccessModel,
+				SendLast, PresenceSubscription, RosterGroup,
+				Options).
+
+unsubscribe_node(NodeID, Sender, Subscriber, SubID) ->
+    node_hometree:unsubscribe_node(NodeID, Sender, Subscriber, SubID).
+
+publish_item(NodeID, Publisher, Model, MaxItems, ItemID, Payload) ->
+    node_hometree:publish_item(NodeID, Publisher, Model, MaxItems,
+			      ItemID, Payload).
+
+remove_extra_items(NodeID, MaxItems, ItemIDs) ->
+    node_hometree:remove_extra_items(NodeID, MaxItems, ItemIDs).
+
+delete_item(NodeID, Publisher, PublishModel, ItemID) ->
+    node_hometree:delete_item(NodeID, Publisher, PublishModel, ItemID).
+
+purge_node(NodeID, Owner) ->
+    node_hometree:purge_node(NodeID, Owner).
+
+get_entity_affiliations(Host, Owner) ->
+    node_hometree:get_entity_affiliations(Host, Owner).
+
+get_node_affiliations(NodeID) ->
+    node_hometree:get_node_affiliations(NodeID).
+
+get_affiliation(NodeID, Owner) ->
+    node_hometree:get_affiliation(NodeID, Owner).
+
+set_affiliation(NodeID, Owner, Affiliation) ->
+    node_hometree:set_affiliation(NodeID, Owner, Affiliation).
+
+get_entity_subscriptions(Host, Owner) ->
+    node_hometree:get_entity_subscriptions(Host, Owner).
+
+get_node_subscriptions(NodeID) ->
+    node_hometree:get_node_subscriptions(NodeID).
+
+get_subscriptions(NodeID, Owner) ->
+    node_hometree:get_subscriptions(NodeID, Owner).
+
+set_subscriptions(NodeID, Owner, Subscriptions) ->
+    node_hometree:set_subscriptions(NodeID, Owner, Subscriptions).
+
+get_states(NodeID) ->
+    node_hometree:get_states(NodeID).
+
+get_state(NodeID, JID) ->
+    node_hometree:get_state(NodeID, JID).
+
+set_state(State) ->
+    node_hometree:set_state(State).
+
+get_items(NodeID, From) ->
+    node_hometree:get_items(NodeID, From).
+
+get_items(NodeID, JID, AccessModel, PresenceSubscription,
+	  RosterGroup, SubID) ->
+    node_hometree:get_items(NodeID, JID, AccessModel, PresenceSubscription,
+			   RosterGroup, SubID).
+
+get_item(NodeID, ItemID) ->
+    node_hometree:get_item(NodeID, ItemID).
+
+get_item(NodeID, ItemID, JID, AccessModel, PresenceSubscription,
+	 RosterGroup, SubID) ->
+    node_hometree:get_item(NodeID, ItemID, JID, AccessModel,
+			  PresenceSubscription, RosterGroup, SubID).
+
+set_item(Item) ->
+    node_hometree:set_item(Item).
+
+get_item_name(Host, Node, ID) ->
+    node_hometree:get_item_name(Host, Node, ID).
diff --git a/src/mod_pubsub/node_dispatch.erl b/src/mod_pubsub/node_dispatch.erl
index 5661b39e9..f67ab81fa 100644
--- a/src/mod_pubsub/node_dispatch.erl
+++ b/src/mod_pubsub/node_dispatch.erl
@@ -76,8 +76,7 @@ terminate(Host, ServerHost) ->
     node_hometree:terminate(Host, ServerHost).
 
 options() ->
-    [{node_type, dispatch},
-     {deliver_payloads, true},
+    [{deliver_payloads, true},
      {notify_config, false},
      {notify_delete, false},
      {notify_retract, true},
@@ -129,7 +128,7 @@ publish_item(NodeId, Publisher, Model, MaxItems, ItemId, Payload) ->
 			  node_hometree:publish_item(
 			    SubNode#pubsub_node.id, Publisher, Model,
 			    MaxItems, ItemId, Payload)
-		  end, nodetree_default:get_subnodes(NodeId, Publisher)).
+		  end, nodetree_tree:get_subnodes(NodeId, Publisher, Publisher)).
 
 remove_extra_items(_NodeId, _MaxItems, ItemIds) ->
     {result, {ItemIds, []}}.
diff --git a/src/mod_pubsub/node_flat.erl b/src/mod_pubsub/node_flat.erl
index c530cf934..a4fbb3b67 100644
--- a/src/mod_pubsub/node_flat.erl
+++ b/src/mod_pubsub/node_flat.erl
@@ -69,8 +69,7 @@ terminate(Host, ServerHost) ->
     node_hometree:terminate(Host, ServerHost).
 
 options() ->
-    [{node_type, flat},
-     {deliver_payloads, true},
+    [{deliver_payloads, true},
      {notify_config, false},
      {notify_delete, false},
      {notify_retract, true},
diff --git a/src/mod_pubsub/node_hometree.erl b/src/mod_pubsub/node_hometree.erl
index 77acfdd94..45c695ae2 100644
--- a/src/mod_pubsub/node_hometree.erl
+++ b/src/mod_pubsub/node_hometree.erl
@@ -132,8 +132,7 @@ terminate(_Host, _ServerHost) ->
 %%	  {send_last_published_item, never},
 %%	  {presence_based_delivery, false}]'''
 options() ->
-    [{node_type, default},
-     {deliver_payloads, true},
+    [{deliver_payloads, true},
      {notify_config, false},
      {notify_delete, false},
      {notify_retract, true},
@@ -597,7 +596,7 @@ get_entity_affiliations(Host, Owner) ->
     States = mnesia:match_object(#pubsub_state{stateid = {GenKey, '_'}, _ = '_'}),
     NodeTree = case ets:lookup(gen_mod:get_module_proc(Host, config), nodetree) of
 	    [{nodetree, N}] -> N;
-	    _ -> nodetree_default
+	    _ -> nodetree_tree
 	end,
     Reply = lists:foldl(fun(#pubsub_state{stateid = {_, N}, affiliation = A}, Acc) ->
 	case NodeTree:get_node(N) of
@@ -654,7 +653,7 @@ get_entity_subscriptions(Host, Owner) ->
     end,
     NodeTree = case ets:lookup(gen_mod:get_module_proc(Host, config), nodetree) of
 	    [{nodetree, N}] -> N;
-	    _ -> nodetree_default
+	    _ -> nodetree_tree
 	end,
     Reply = lists:foldl(fun(#pubsub_state{stateid = {J, N}, subscriptions = Ss}, Acc) ->
 	case NodeTree:get_node(N) of
@@ -774,9 +773,10 @@ get_items(NodeId, JID, AccessModel, PresenceSubscription, RosterGroup, _SubId) -
     SubKey = jlib:jid_tolower(JID),
     GenKey = jlib:jid_remove_resource(SubKey),
     GenState = get_state(NodeId, GenKey),
+    SubState = get_state(NodeId, SubKey),
     Affiliation = GenState#pubsub_state.affiliation,
-    Subscription = GenState#pubsub_state.subscriptions,
-    Whitelisted = can_fetch_item(Affiliation, Subscription),
+    Subscriptions = SubState#pubsub_state.subscriptions,
+    Whitelisted = can_fetch_item(Affiliation, Subscriptions),
     if
 	%%SubID == "", ?? ->
 	    %% Entity has multiple subscriptions to the node but does not specify a subscription ID
@@ -796,7 +796,7 @@ get_items(NodeId, JID, AccessModel, PresenceSubscription, RosterGroup, _SubId) -
 	(AccessModel == whitelist) and (not Whitelisted) ->
 	    %% Node has whitelist access model and entity lacks required affiliation
 	    {error, ?ERR_EXTENDED(?ERR_NOT_ALLOWED, "closed-node")};
-	(AccessModel == authorize) -> % TODO: to be done
+	(AccessModel == authorize) and (not Whitelisted) ->
 	    %% Node has authorize access model
 	    {error, ?ERR_FORBIDDEN};
 	%%MustPay ->
@@ -887,8 +887,10 @@ can_fetch_item(owner,        _)             -> true;
 can_fetch_item(member,       _)             -> true;
 can_fetch_item(publisher,    _)             -> true;
 can_fetch_item(outcast,      _)             -> false;
-can_fetch_item(none,         subscribed)    -> true;
-can_fetch_item(none,         none)          -> false;
+can_fetch_item(none, Subscriptions) ->
+    lists:any(fun ({subscribed, _SubID}) -> true;
+                  (_)                    -> false
+              end, Subscriptions);
 can_fetch_item(_Affiliation, _Subscription) -> false.
 
 %% Returns the first item where Pred() is true in List
diff --git a/src/mod_pubsub/node_mb.erl b/src/mod_pubsub/node_mb.erl
index af8e9222b..70ceabbb1 100644
--- a/src/mod_pubsub/node_mb.erl
+++ b/src/mod_pubsub/node_mb.erl
@@ -81,8 +81,7 @@ terminate(Host, ServerHost) ->
     ok.
 
 options() ->
-    [{node_type, pep},
-     {deliver_payloads, true},
+    [{deliver_payloads, true},
      {notify_config, false},
      {notify_delete, false},
      {notify_retract, false},
diff --git a/src/mod_pubsub/node_pep.erl b/src/mod_pubsub/node_pep.erl
index 5ef3bff70..8e2e7e0a3 100644
--- a/src/mod_pubsub/node_pep.erl
+++ b/src/mod_pubsub/node_pep.erl
@@ -76,8 +76,7 @@ terminate(Host, ServerHost) ->
     ok.
 
 options() ->
-    [{node_type, pep},
-     {deliver_payloads, true},
+    [{deliver_payloads, true},
      {notify_config, false},
      {notify_delete, false},
      {notify_retract, false},
@@ -174,7 +173,7 @@ get_entity_affiliations(_Host, Owner) ->
     States = mnesia:match_object(#pubsub_state{stateid = {GenKey, '_'}, _ = '_'}),
     NodeTree = case ets:lookup(gen_mod:get_module_proc(D, config), nodetree) of
 	    [{nodetree, N}] -> N;
-	    _ -> nodetree_default
+	    _ -> nodetree_tree
 	end,
     Reply = lists:foldl(fun(#pubsub_state{stateid = {_, N}, affiliation = A}, Acc) ->
 	case NodeTree:get_node(N) of
@@ -206,7 +205,7 @@ get_entity_subscriptions(_Host, Owner) ->
     end,
     NodeTree = case ets:lookup(gen_mod:get_module_proc(D, config), nodetree) of
 	    [{nodetree, N}] -> N;
-	    _ -> nodetree_default
+	    _ -> nodetree_tree
 	end,
     Reply = lists:foldl(fun(#pubsub_state{stateid = {J, N}, subscriptions = Ss}, Acc) ->
 	case NodeTree:get_node(N) of
diff --git a/src/mod_pubsub/node_private.erl b/src/mod_pubsub/node_private.erl
index d62365ba6..e9c925403 100644
--- a/src/mod_pubsub/node_private.erl
+++ b/src/mod_pubsub/node_private.erl
@@ -78,8 +78,7 @@ terminate(Host, ServerHost) ->
     node_hometree:terminate(Host, ServerHost).
 
 options() ->
-    [{node_type, private},
-     {deliver_payloads, true},
+    [{deliver_payloads, true},
      {notify_config, false},
      {notify_delete, false},
      {notify_retract, true},
diff --git a/src/mod_pubsub/node_public.erl b/src/mod_pubsub/node_public.erl
index cc753c847..ae7beff84 100644
--- a/src/mod_pubsub/node_public.erl
+++ b/src/mod_pubsub/node_public.erl
@@ -78,8 +78,7 @@ terminate(Host, ServerHost) ->
     node_hometree:terminate(Host, ServerHost).
 
 options() ->
-    [{node_type, public},
-     {deliver_payloads, true},
+    [{deliver_payloads, true},
      {notify_config, false},
      {notify_delete, false},
      {notify_retract, true},
diff --git a/src/mod_pubsub/nodetree_dag.erl b/src/mod_pubsub/nodetree_dag.erl
new file mode 100644
index 000000000..1a5921fb8
--- /dev/null
+++ b/src/mod_pubsub/nodetree_dag.erl
@@ -0,0 +1,246 @@
+%%% ====================================================================
+%%% ``The contents of this file are subject to the Erlang Public License,
+%%% Version 1.1, (the "License"); you may not use this file except in
+%%% compliance with the License. You should have received a copy of the
+%%% Erlang Public License along with this software. If not, it can be
+%%% retrieved via the world wide web at http://www.erlang.org/.
+%%%
+%%% Software distributed under the License is distributed on an "AS IS"
+%%% basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
+%%% the License for the specific language governing rights and limitations
+%%% under the License.
+%%%
+%%% @author Brian Cully <bjc@kublai.com>
+%%% @version {@vsn}, {@date} {@time}
+%%% @end
+%%% ====================================================================
+
+-module(nodetree_dag).
+-author('bjc@kublai.com').
+
+%% API
+-export([init/3,
+	 terminate/2,
+	 options/0,
+	 set_node/1,
+	 get_node/3,
+	 get_node/2,
+	 get_node/1,
+	 get_nodes/2,
+	 get_nodes/1,
+	 get_parentnodes/3,
+	 get_parentnodes_tree/3,
+	 get_subnodes/3,
+	 get_subnodes_tree/3,
+	 create_node/5,
+	 delete_node/2]).
+
+-include_lib("stdlib/include/qlc.hrl").
+
+-include("ejabberd.hrl").
+-include("pubsub.hrl").
+-include("jlib.hrl").
+
+-behaviour(gen_pubsub_nodetree).
+
+-define(DEFAULT_NODETYPE, leaf).
+-define(DEFAULT_PARENTS, []).
+-define(DEFAULT_CHILDREN, []).
+
+-compile(export_all).
+
+%%====================================================================
+%% API
+%%====================================================================
+init(Host, ServerHost, Opts) ->
+    nodetree_tree:init(Host, ServerHost, Opts),
+    mnesia:transaction(fun create_node/5,
+		       [Host, [], "default", service_jid(ServerHost), []]).
+
+terminate(Host, ServerHost) ->
+    nodetree_tree:terminate(Host, ServerHost).
+
+create_node(Key, NodeID, Type, Owner, Options) ->
+    OwnerJID = jlib:jid_tolower(jlib:jid_remove_resource(Owner)),
+    case find_node(Key, NodeID) of
+	false ->
+	    ID = pubsub_index:new(node),
+	    N = #pubsub_node{nodeid = oid(Key, NodeID),
+			     id = ID,
+			     type = Type,
+			     owners = [OwnerJID],
+			     options = Options},
+	    case set_node(N) of
+		ok    -> {ok, ID};
+		Other -> Other
+	    end;
+	_ ->
+	    {error, ?ERR_CONFLICT}
+    end.
+
+set_node(#pubsub_node{nodeid  = {Key, _},
+		      owners  = Owners,
+		      options = Options} = Node) ->
+    Parents = find_opt(collection, ?DEFAULT_PARENTS,  Options),
+    case validate_parentage(Key, Owners, Parents) of
+	true ->
+	    %% Update parents whenever the config changes.
+	    mnesia:write(Node#pubsub_node{parents = Parents});
+	Other ->
+	    Other
+    end.
+
+delete_node(Key, NodeID) ->
+    case find_node(Key, NodeID) of
+	false ->
+	    {error, ?ERR_ITEM_NOT_FOUND};
+	Node ->
+	    %% Find all of N's children, update their configs to
+	    %% remove N from the collection setting.
+	    lists:foreach(fun (#pubsub_node{options = Opts} = Child) ->
+				  NewOpts = remove_config_parent(NodeID, Opts),
+				  Parents = find_opt(collection, ?DEFAULT_PARENTS, NewOpts),
+				  ok = mnesia:write(pubsub_node,
+						    Child#pubsub_node{
+						      parents = Parents,
+						      options = NewOpts},
+						    write)
+			  end, get_subnodes(Key, NodeID)),
+
+	    %% Remove and return the requested node.
+	    mnesia:delete_object(pubsub_node, Node, write),
+	    [Node]
+    end.
+
+options() ->
+    nodetree_tree:options().
+
+get_node(Host, NodeID, _From) ->
+    get_node(Host, NodeID).
+
+get_node(Host, NodeID) ->
+    case find_node(Host, NodeID) of
+	false -> {error, ?ERR_ITEM_NOT_FOUND};
+	Node  -> Node
+    end.
+
+get_node(NodeId) ->
+    nodetree_tree:get_node(NodeId).
+
+get_nodes(Key, From) ->
+    nodetree_tree:get_nodes(Key, From).
+
+get_nodes(Key) ->
+    nodetree_tree:get_nodes(Key).
+
+get_parentnodes(Host, NodeID, _From) ->
+    case find_node(Host, NodeID) of
+	false -> {error, ?ERR_ITEM_NOT_FOUND};
+	#pubsub_node{parents = Parents} ->
+	    Q = qlc:q([N || #pubsub_node{nodeid = {NHost, NNode}} = N <- mnesia:table(pubsub_node),
+			    Parent <- Parents,
+			    Host == NHost,
+			    Parent == NNode]),
+	    qlc:e(Q)
+    end.
+
+get_parentnodes_tree(Host, NodeID, _From) ->
+    Pred = fun (NID, #pubsub_node{nodeid = {_, NNodeID}}) ->
+		   NID == NNodeID
+	   end,
+    Tr = fun (#pubsub_node{parents = Parents}) -> Parents end,
+    traversal_helper(Pred, Tr, Host, [NodeID]).
+
+get_subnodes(Host, NodeID, _From) ->
+    get_subnodes(Host, NodeID).
+
+get_subnodes(Host, NodeID) ->
+    case find_node(Host, NodeID) of
+	false -> {error, ?ERR_ITEM_NOT_FOUND};
+	_ ->
+	    Q = qlc:q([Node || #pubsub_node{nodeid  = {NHost, _},
+					    parents = Parents} = Node <- mnesia:table(pubsub_node),
+			       Host == NHost,
+			       lists:member(NodeID, Parents)]),
+	    qlc:e(Q)
+    end.
+
+get_subnodes_tree(Host, NodeID, _From) ->
+    Pred = fun (NID, #pubsub_node{parents = Parents}) ->
+		   lists:member(NID, Parents)
+	   end,
+    Tr = fun (#pubsub_node{nodeid = {_, N}}) -> N end,
+    traversal_helper(Pred, Tr, Host, [NodeID]).
+
+%%====================================================================
+%% Internal functions
+%%====================================================================
+oid(Key, Name) -> {Key, Name}.
+
+%% Key    = jlib:jid() | host()
+%% NodeID = string()
+find_node(Key, NodeID) ->
+    case mnesia:read(pubsub_node, oid(Key, NodeID), read) of
+	[]     -> false;
+	[Node] -> Node
+    end.
+
+%% Key     = jlib:jid() | host()
+%% Default = term()
+%% Options = [{Key = atom(), Value = term()}]
+find_opt(Key, Default, Options) ->
+    case lists:keysearch(Key, 1, Options) of
+	{value, {Key, Val}} -> Val;
+	_		   -> Default
+    end.
+
+traversal_helper(Pred, Tr, Host, NodeIDs) ->
+    traversal_helper(Pred, Tr, 0, Host, NodeIDs, []).
+
+traversal_helper(_Pred, _Tr, _Depth, _Host, [], Acc) ->
+    Acc;
+traversal_helper(Pred, Tr, Depth, Host, NodeIDs, Acc) ->
+    Q = qlc:q([Node || #pubsub_node{nodeid = {NHost, _}} = Node <- mnesia:table(pubsub_node),
+		       NodeID <- NodeIDs,
+		       Host   == NHost,
+		       Pred(NodeID, Node)]),
+    Nodes = qlc:e(Q),
+    IDs = lists:flatmap(Tr, Nodes),
+    traversal_helper(Pred, Tr, Depth + 1, Host, IDs, [{Depth, Nodes} | Acc]).
+
+remove_config_parent(NodeID, Options) ->
+    remove_config_parent(NodeID, Options, []).
+
+remove_config_parent(_NodeID, [], Acc) ->
+    lists:reverse(Acc);
+remove_config_parent(NodeID, [{collection, Parents} | T], Acc) ->
+    remove_config_parent(NodeID, T,
+			 [{collection, lists:delete(NodeID, Parents)} | Acc]);
+remove_config_parent(NodeID, [H | T], Acc) ->
+    remove_config_parent(NodeID, T, [H | Acc]).
+
+validate_parentage(_Key, _Owners, []) ->
+    true;
+validate_parentage(Key, Owners, [[] | T]) ->
+    validate_parentage(Key, Owners, T);
+validate_parentage(Key, Owners, [ParentID | T]) ->
+    case find_node(Key, ParentID) of
+	false -> {error, ?ERR_ITEM_NOT_FOUND};
+	#pubsub_node{owners = POwners, options = POptions} ->
+	    NodeType = find_opt(node_type, ?DEFAULT_NODETYPE, POptions),
+	    MutualOwners = [O || O <- Owners, PO <- POwners,
+				 O == PO],
+	    case {MutualOwners, NodeType} of
+		{[], _}	 -> {error, ?ERR_NOT_ALLOWED};
+		{_, collection} -> validate_parentage(Key, Owners, T)
+	    end
+    end.
+
+%% @spec (Host) -> jid()
+%%	Host = host()
+%% @doc <p>Generate pubsub service JID.</p>
+service_jid(Host) ->
+    case Host of
+	{U,S,_} -> {jid, U, S, "", U, S, ""};
+	_       -> {jid, "", Host, "", "", Host, ""}
+    end.
diff --git a/src/mod_pubsub/nodetree_tree.erl b/src/mod_pubsub/nodetree_tree.erl
index 8f49a06b0..767b0e9c8 100644
--- a/src/mod_pubsub/nodetree_tree.erl
+++ b/src/mod_pubsub/nodetree_tree.erl
@@ -36,6 +36,8 @@
 -module(nodetree_tree).
 -author('christophe.romain@process-one.net').
 
+-include_lib("stdlib/include/qlc.hrl").
+
 -include("pubsub.hrl").
 -include("jlib.hrl").
 
@@ -50,6 +52,8 @@
 	 get_node/1,
 	 get_nodes/2,
 	 get_nodes/1,
+	 get_parentnodes/3,
+	 get_parentnodes_tree/3,
 	 get_subnodes/3,
 	 get_subnodes_tree/3,
 	 create_node/5,
@@ -124,6 +128,32 @@ get_nodes(Host, _From) ->
 get_nodes(Host) ->
     mnesia:match_object(#pubsub_node{nodeid = {Host, '_'}, _ = '_'}).
 
+%% @spec (Host, Node, From) -> [{Depth, Record}] | {error, Reason}
+%%     Host   = mod_pubsub:host() | mod_pubsub:jid()
+%%     Node   = mod_pubsub:pubsubNode()
+%%     From   = mod_pubsub:jid()
+%%     Depth  = integer()
+%%     Record = pubsubNode()
+%% @doc <p>Default node tree does not handle parents, return empty list.</p>
+get_parentnodes(_Host, _Node, _From) ->
+    [].
+
+%% @spec (Host, Node, From) -> [{Depth, Record}] | {error, Reason}
+%%     Host   = mod_pubsub:host() | mod_pubsub:jid()
+%%     Node   = mod_pubsub:pubsubNode()
+%%     From   = mod_pubsub:jid()
+%%     Depth  = integer()
+%%     Record = pubsubNode()
+%% @doc <p>Default node tree does not handle parents, return a list
+%% containing just this node.</p>
+get_parentnodes_tree(Host, Node, From) ->
+    case get_node(Host, Node, From) of
+	N when is_record(N, pubsub_node) ->
+	    [{0, mnesia:read(pubsub_node, {Host, Node})}];
+	Error ->
+	    Error
+    end.
+
 %% @spec (Host, Node, From) -> [pubsubNode()] | {error, Reason}
 %%     Host = mod_pubsub:host()
 %%     Node = mod_pubsub:pubsubNode()
@@ -131,7 +161,11 @@ get_nodes(Host) ->
 get_subnodes(Host, Node, _From) ->
     get_subnodes(Host, Node).
 get_subnodes(Host, Node) ->
-    mnesia:match_object(#pubsub_node{nodeid = {Host, '_'}, parent = Node, _ = '_'}).
+    Q = qlc:q([N || #pubsub_node{nodeid = {NHost, _},
+				 parents = Parents} = N <- mnesia:table(pubsub_node),
+		       Host == NHost,
+		       lists:member(Node, Parents)]),
+    qlc:e(Q).
 
 %% @spec (Host, Index) -> [pubsubNodeIdx()] | {error, Reason}
 %%     Host = mod_pubsub:host()
@@ -180,7 +214,7 @@ create_node(Host, Node, Type, Owner, Options) ->
 		    NodeId = pubsub_index:new(node),
 		    mnesia:write(#pubsub_node{nodeid = {Host, Node},
 					      id = NodeId,
-					      parent = ParentNode,
+					      parents = [ParentNode],
 					      type = Type,
 					      owners = [BJID],
 					      options = Options}),
diff --git a/src/mod_pubsub/nodetree_virtual.erl b/src/mod_pubsub/nodetree_virtual.erl
index 4b331aeb9..e003f9058 100644
--- a/src/mod_pubsub/nodetree_virtual.erl
+++ b/src/mod_pubsub/nodetree_virtual.erl
@@ -47,6 +47,8 @@
 	 get_node/1,
 	 get_nodes/2,
 	 get_nodes/1,
+	 get_parentnodes/3,
+	 get_parentnodes_tree/3,
 	 get_subnodes/3,
 	 get_subnodes_tree/3,
 	 create_node/5,
@@ -109,6 +111,22 @@ get_nodes(_Host) ->
 %%     Node = mod_pubsub:pubsubNode()
 %%     From = mod_pubsub:jid()
 %% @doc <p>Virtual node tree does not handle parent/child. Child list is empty.</p>
+get_parentnodes(_Host, _Node, _From) ->
+    [].
+
+%% @spec (Host, Node, From) -> [pubsubNode()]
+%%     Host = mod_pubsub:host()
+%%     Node = mod_pubsub:pubsubNode()
+%%     From = mod_pubsub:jid()
+%% @doc <p>Virtual node tree does not handle parent/child. Child list is empty.</p>
+get_parentnodes_tree(_Host, _Node, _From) ->
+    [].
+
+%% @spec (Host, Node, From) -> [pubsubNode()]
+%%     Host = mod_pubsub:host()
+%%     Node = mod_pubsub:pubsubNode()
+%%     From = mod_pubsub:jid()
+%% @doc <p>Virtual node tree does not handle parent/child. Child list is empty.</p>
 get_subnodes(Host, Node, _From) ->
     get_subnodes(Host, Node).
 get_subnodes(_Host, _Node) ->
diff --git a/src/mod_pubsub/pubsub.hrl b/src/mod_pubsub/pubsub.hrl
index ee129aa9f..f406a05c3 100644
--- a/src/mod_pubsub/pubsub.hrl
+++ b/src/mod_pubsub/pubsub.hrl
@@ -91,7 +91,7 @@
 %%% <p>The <tt>parentid</tt> and <tt>type</tt> fields are indexed.</p>
 -record(pubsub_node, {nodeid,
 		      id,
-		      parent,
+		      parents = [],
 		      type = "flat",
 		      owners = [],
 		      options = []